1. Field of the Invention
The invention pertains to a device and a method for filling or packing containers with contents, especially with beverages, food products, medications, etc. While the containers travel through the device from an entrance side to an exit side, the containers passing through the working space are treated with a sterile fluid, especially sterile air, to prevent microbial contamination. The sterile atmosphere in the working space must be maintained until the process of sealing the containers has been completed inside the working space.
2. Description of the Related Art
After a large number of containers has been transported through the working space and the containers have been filled or packed, the working space is cleaned. Water, alkaline or acid-based foam products, and hydrogen peroxide (H2O2) aerosols in particular are considered suitable cleaning agents.
A device for the aseptic packing of containers with food products and other products inside a working space is known from U.S. Pat. No. 3,783,581. The packaging containers travel through it from an entrance side to an exit side. A sterile atmosphere is maintained in the working space by the use of several gas distribution pipes arranged underneath it, which feed high-temperature steam or superheated air into the working space.
From DE 10 2005 004 658 B3, it is known that sterile air can be blown into the entire working space of the filling machine to produce a clean-room atmosphere. The sterile air is supplied through at least one hose, which is installed in the area of the ceiling zone of the working space; this hose is connected to a feed for the sterile air and comprises a plurality of holes, the number, distribution, and size of which are adapted to the working space to be supplied. The hose is intended for a single use. The idea behind using the hose only once is to save the cost, which would otherwise be considerable, of cleaning the gas distribution pipes between two filling operations, after the containers have been transported through the working space.
A feed device for a cleaning medium arranged in an aseptic working space is known from EP 0 427 348 A1; to clean the aseptic working space, the device comprises two pipes extending laterally along the sides of the working space. Each pipe comprises a plurality of spray openings and can be supplied with a cleaning medium. The cleaning medium is supplied under pressure to the two spray pipes while the pipes are being rotated. The cleaning medium emerging under pressure from the spray openings forms a circular jet.
A device for sterilizing objects such as glass bottles in a closed chamber is known from U.S. Pat. No. 5,022,165 A. The glass bottles are conveyed through the device from an entrance to an exit while they are exposed to an elevated temperature. In a preheating zone, a perforated plate above the objects distributes preheated air over the glass bottles.
DE 33 23 710 A1 discloses a gas treatment device for containers being transported on a conveyor. A channel is arranged above the conveyor and follows its course. A distributor pipe comprising openings for a sterile gas is installed in the channel. The sterile gas supplied by the distributor pipe enters the containers through a porous wall arranged in the channel underneath the distributor pipe. The porous wall concentrates the sterile gas on the area of the container openings, whereas the other container parts can be exposed to the influence of surrounding air.